Vector-like quarks with a scalar triplet

Abstract

We study a minimal extension to the Standard Model with an additional real scalar triplet, $\Sigma$, and a single vector-like quark, $T$. This class of models appear naturally in extensions of the Littlest Higgs model that incorporate dark matter without the need of $T$-parity. We assume the limit that the triplet does not develop a vacuum expectation value and that all dimension five operators coupling the triplet to Standard Model fields and the vector-like quarks are characterized by the scale $\Lambda$ at which we expect new physics to arise. We introduce new non-renormalizable interactions between the new scalar sector and fermion sector that allow mixing between the Standard Model third generation up-type quark and the vector-like quark in a way that leads to the cancellation of the leading quadratic divergences to the one-loop corrections from the top quark to the mass of the Higgs boson. Within this framework, new decay modes of the vector-like quark to the real scalar triplet and SM particles arise and bring forth an opportunity to probe this model with existing and future LHC data. We contrast constraints from direct colliders searches with low energy precision measurements and find that heavy vector-like top quarks with a mass as low as $650$ GeV are consistent with current experimental constraints in models where new physics arises at scales below $2$ TeV.

References in corpus (16)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• -- HATHOR -- HAdronic Top and Heavy quarks crOss section calculatoR
• A custodial symmetry for Zbb
• Light custodians in natural composite Higgs models
• Measurement of the single-top-quark t-channel cross section in pp collisions at sqrt(s) = 7 TeV
• The Inert Dark Matter
• Triplet Scalars and Dark Matter at the LHC
• Stabilizing Electroweak Vacuum in a Vector-like Fermion Model
• (Non)decoupling of the Higgs triplet effects
• Search for flavor changing neutral currents via quark-gluon couplings in single top quark production using 2.3 fb^-1 of ppbar collisions
• Higgs Triplets and Limits from Precision Measurements
• Framework for Model Independent Analyses of Multiple Extra Quark Scenarios
• Low-Energy Effective Theory, Unitarity, and Non-Decoupling Behavior in a Model with Heavy Higgs-Triplet Fields
• T-parity, its problems and their solution
• New signals for singlet Higgs and vector-like quarks at the LHC
• Vector Quarks in the Higgs Triplet Model